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Talk:COLORMAP
This page is factually inaccurate: a brightness value of 7 does use the lowest brightness level, but colormap entry 0 is the brightest. I can't think of an easy way of expressing this right now so I'll leave it as a TODO. -- Jdowland 12:43, 26 Mar 2005 (EST) : I have taken a stab at it. radius 16:09, 29 Mar 2005 (EST) :: cheers :) Looks good. I've been doing a lot of digging in the COLORMAPs over easter and I may be able to add a lot more info here (info which has been overlooked in the UDS etc.) Jdowland 02:18, 30 Mar 2005 (EST) :::This is all very wrong. There is no constant colormap used for a sector of a particular light level, as light levels fade with distance from the viewer. Even a brightness 0 sector uses reasonably bright colormaps at point blank range. Is paragraph 3 supposed to be talking about the infinite distance colormap? 71.58.109.233 18:50, 4 October 2007 (UTC) ::::Got a few concrete references. In linuxdoom-1.10 source, r_plane.c . Lines 428-437 in R_DrawPlanes(), executed once per visplane, set up the lighting lookup table based on the sector light level and the z distance from the plane to the viewing location. Lines 161-171 in R_MapPlane(), executed once per span, compute the final colormap given to drawspan based on the lookup table from R_DrawPlanes() and the distance in the (x,y) plane between viewer and the span to draw. Most of the wall lighting is in r_segs.c, where things get more complicated because walls get lighted differently based on their compass direction (I still can't believe it took me 5 years to notice that...). I'm removing the incorrect information. 71.58.109.233 02:48, 5 October 2007 (UTC) ::::: Even a brightness 0 sector uses reasonably bright colormaps at point blank range. Heh, it does indeed — you too can complete max runs of EP.WAD from Maximum Doom. ::::: because walls get lighted differently based on their compass direction Hardly a capital offense to think of this as obscure: see http://www.doomworld.com/vb/doom-general/44233-light-rendering-on-vanilla-doom/. Ryan W 15:49, 1 October 2008 (UTC) :::::::Even a brightness 0 sector uses reasonably bright colormaps at point blank range. ::::::No, it uses the darkest one always. It's similar to its opposite, level 256, which always applies full brightness without any light diminishing. In fact, if lighting is 0-15, gun flashes don't have any effect on the sector (but might affect nearby ones). I'm not sure if this is because the value is 0, or what, but that's how it is. Boom (and some engines that took code from it) altered this, making levels 0-15 brighter near walls. See this WAD. Run it under Doom-plus, Strawberry Doom or DOSDoom v0.47 (plain Doom can't take the number of visplanes). Some other source ports (Boom, PrBoom, ZDoom, &c) use the Boom-derived lighting method or something similar, producing the effect you describe. No idea why the Boom coders changed the behavior of lighting... as far as I'm concerned that's just a bug or error. Note also that the linedefs that lower light to "fully dark" don't really use the darkest level, but one or two before it. Who is like God? 09:26, 3 October 2008 (UTC)